Data from: Mean and variance of phylogenetic trees

We describe the use of the Fréchet mean and variance in the
Billera-Holmes-Vogtmann (BHV) treespace to summarize and explore the
diversity of a set of phylogenetic trees. We show that the Fréchet mean is
comparable to other summary methods, and, despite its stickiness property,
is more likely to be binary than the majority-rules consensus tree. We
show that the Fréchet variance is faster and more precise than commonly
used variance measures. The Fréchet mean and variance are more
theoretically justified, and more robust, than previous estimates of this
type, and can be estimated reasonably efficiently, providing a foundation
for building more advanced statistical methods and leading to applications
such as mean hypothesis testing and outlier detection.